Re: include/linux/fortify-string.h:414:4: error: call to '__read_overflow' declared with 'error' attribute: detected read beyond size of object (1st parameter)

[Nathan Chancellor <nathan@kernel.org>]

On Wed, Feb 08, 2023 at 02:59:05AM +0800, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head:   05ecb680708a1dbe6554d6fc17e5d9a8a7cb5e6a
> commit: 925d046e7e52c71c3531199ce137e141807ef740 RDMA/core: Add a netevent notifier to cma
> date:   8 months ago
> config: mips-buildonly-randconfig-r006-20230207 (https://download.01.org/0day-ci/archive/20230208/202302080231.ZqOmpanX-lkp@intel.com/config)
> compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project db0e6591612b53910a1b366863348bdb9d7d2fb1)
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # install mips cross compiling tool for clang build
>         # apt-get install binutils-mips-linux-gnu
>         # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=925d046e7e52c71c3531199ce137e141807ef740
>         git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
>         git fetch --no-tags linus master
>         git checkout 925d046e7e52c71c3531199ce137e141807ef740
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=mips olddefconfig
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash drivers/infiniband/
> 
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
> 
> All errors (new ones prefixed by >>):
> 
>    In file included from drivers/infiniband/core/cma.c:9:
>    In file included from include/linux/completion.h:12:
>    In file included from include/linux/swait.h:7:
>    In file included from include/linux/spinlock.h:55:
>    In file included from include/linux/preempt.h:78:
>    In file included from ./arch/mips/include/generated/asm/preempt.h:1:
>    In file included from include/asm-generic/preempt.h:5:
>    In file included from include/linux/thread_info.h:60:
>    In file included from arch/mips/include/asm/thread_info.h:16:
>    In file included from arch/mips/include/asm/processor.h:15:
>    In file included from include/linux/cpumask.h:12:
>    In file included from include/linux/bitmap.h:11:
>    In file included from include/linux/string.h:253:
> >> include/linux/fortify-string.h:414:4: error: call to '__read_overflow' declared with 'error' attribute: detected read beyond size of object (1st parameter)
>                            __read_overflow();
>                            ^
>    1 error generated.

This is tentatively a bug in clang, although I do not see KASAN enabled:

https://github.com/ClangBuiltLinux/linux/issues/1687

I do see CONFIG_UBSAN_BOOL=y though, so this could be a generic
sanitizer problem.

Cheers,
Nathan